Hyrel says it wants to change the economics of 3D printing. If the fact that you're still talking at least a couple thousand bucks just to buy the machine makes you balk at that claim, consider that unlike other 3D printers, it can make more than one item at a time, thereby cutting down on both printing time and material waste. It's also versatile, able to print with a wide variety of materials and even print flexible goods.

Kevvox, on the other hand, isn't interested in changing the economics of 3D printing -- you're talking at least $17,000 per unit -- but it is interested in pushing the boundaries of quality and precision. At least your large cash outlay also gets you some integrated software, which makes the entire printing workflow, from design to extrusion, much easier, and the company claims the machine is capable of making industrial-grade parts.

This is the coolest gadget of the bunch by far: 3Doodler's 3D-printing pen. Load it with the color of your choice, and start drawing. Rather than putting ink on a page, it puts plastic in 3D space. Yeah, you make by drawing. It's the closest we've come yet to making "Harold and the Purple Crayon" a reality.

This printer, meanwhile, shows the most promise to change people's lives. The Regenovo doesn't use plastic to make objects; rather, it uses biomaterials to make the likes of muscles and tendons. The company hopes to be able to print repairs for damaged organs or even produce entire artifical organs. If it succeeds, it could change medicine as we know it.

Robox is all about simplicity: It wants to be to 3D printing what point-and-shoot cameras are to photography. It's a fully integrated system (even the extrusion materials have chips built-in to tell the printer what they are), and it's made to be easily upgradeable with planned modules to allow for alternate and/or better modes of printing.

The Xfab sets itself apart by using a printing process called stereolithography in which ultraviolet lasers harden a light-sensitive material (similar to how dentists put fillings in teeth). Using a laser means precision, of course -- it's not called "laser precision" for nothing -- which could give it the edge over extrusion-style printers in some applications.